XE misfire

[Jack]

Having some problems with the Novargh.

Worked fine and dandy up until Saturday morning, when the fuel pump started buzzing really loudly when I started the car (so loud you can clearly hear it both inside and outside the car when <1500rpm). 30 miles on the way to PVS, it developed a misfire on anything over 1/3 throttle but after about another 30 motorway miles it stopped. Coming back, had the same problem all the way home, getting slightly worse.

Had a look at the plugs and leads today - plugs weren't too bad, but I replaced them anyway, and #2 HT lead looked quite badly fouled up (cylinder and plug looked fine though) so I replaced the leads. Still no joy, in fact tonight its even worse - I have quarter throttle (if that) and the car has real problems with hills. Tried to drive through the misfire and the engine just cut out completely, as if the spark or fuel had been cut.

Water is clean, no gunk. It has been drinking a bit of water, but I put this down to an early hose leak (now fixed). Will check water again tomorrow morning though. Oil is clean and I'm not losing any.

Could it be the fuel pump thats causing the misfire? It seems a coincidence that the car has been silly since it started buzzing loudly. Anything else I should check - coil, dizzy?

[meritlover]

fuel pump could be U/S causing low fuel pressure. itl be fine at low revs/load but when you drive harder the duration of the injectors increases and the volume of fuel required increases also, because the pump is sad it wont be able to maintain the pressure/volume required so its giving you a lean burn missfire.
check with what you know.
you know the pump is dodge and they should never run like that, you wouldnt want it to die and breakdown on the road anyway. so i would start by changing it for a happy one!

i hope this helps your poor nova Mr Jack

[Jack]

I was going to purchase a new pump just as a spare in case the current one did go TU.

I've found a couple on ebay - one is rated at 1.1 bar, the other at 7bar. Should I go for the higher one?

[meritlover]

what is the std FP of your XE?

id doubt it would be under 1.1B and even if it was close the pump would be going balls-out all the time, right on its limit. 7B would be better as the FPR will just bleed off the excess anyway.
but do find out properly first!

[burgo]

standard fuel pressure is 3bar i beleave so the 1.1 bar wont work.

id be very careful driving it in a possible under fueling state as to lean is when things start to melt

[Paul]

I have an external MPi pump from a cally 16V, was on my P2 LET. However that was fairly noisy?

[Lee]

Does sound like the pump isn't happy mate.

Easy swap though :) Lucky git LOL

[Jack]

Found a 3 bar one, its half the price of the 7 bar one and brand new, so will give that a shot and see how it goes :)

[Ash]

id be very careful driving it in a possible under fueling state as to lean is when things start to melt

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